The 3’x6’ Pettibon Linked Exercise Trainer is for isometric exercises that stretch and strengthen postural muscles and increase endurance. Exercises in most gyms use isotonic (kinetic) exercises that exercise phasic muscles. Phasic exercises will make one strong; however they will not help and often hinder correction of the spinal subluxation complexes. Kinetic exercises should be discontinued during corrective care. Two people at a time can use the Pettibon Linked Exercise Trainer, making it even more efficient and cost-effective.